Add a mimeHandler extension API.

chrome/browser/resources/pdf/pdf.js

Index: chrome/browser/resources/pdf/pdf.js
diff --git a/chrome/browser/resources/pdf/pdf.js b/chrome/browser/resources/pdf/pdf.js
index 8d2ae0a7c09db35da2c13c5b051a8211a3cc0912..6879e5fb8daf8e3fab6d3f2f35929e32f995fa16 100644
--- a/chrome/browser/resources/pdf/pdf.js
+++ b/chrome/browser/resources/pdf/pdf.js
@@ -71,6 +71,8 @@ function PDFViewer(streamDetails) {
   // positioning, acting as a viewport. The plugin renders into this viewport
   // according to the scroll position of the window.
   this.plugin_ = document.createElement('embed');
+  console.log('created plugin ' + this.plugin_ + ' ' +
+              this.plugin_.postMessage);
   // NOTE: The plugin's 'id' field must be set to 'plugin' since
   // chrome/renderer/printing/print_web_view_helper.cc actually references it.
   this.plugin_.id = 'plugin';
@@ -97,6 +99,8 @@ function PDFViewer(streamDetails) {
   if (!this.streamDetails_.embedded)
     this.plugin_.setAttribute('full-frame', '');
   document.body.appendChild(this.plugin_);
+  console.log('added plugin to DOM ' + this.plugin_ + ' ' +
+              this.plugin_.postMessage);
 
   // Setup the button event listeners.
   $('fit-to-width-button').addEventListener('click',
@@ -404,7 +408,7 @@ PDFViewer.prototype = {
         this.errorScreen_.text = message.data.loadFailedString;
         break;
       case 'cancelStreamUrl':
-        chrome.streamsPrivate.abort(this.streamDetails_.streamUrl);
+        chrome.mimeHandlerPrivate.abortStream();
         break;
     }
   },
@@ -433,6 +437,7 @@ PDFViewer.prototype = {
       chrome.tabs.setZoom(this.streamDetails_.tabId, zoom,
                           this.setZoomComplete_.bind(this, zoom));
     }
+    console.log('afterZoom_ ' + this.plugin_ + ' ' + this.plugin_.postMessage);
     this.plugin_.postMessage({
       type: 'viewport',
       zoom: zoom,